Flameproofing nylon-cotton jersey knit



1 M. a 1-1 5: 2 QRQSSJEEERUB @FWH 119G132 mm? 3 y 1962 J. L. IANNAZZI 3,032,440

FLAMEPROOFING NYLON-COTTON JERSEY KNIT Filed May 26, 1958 TEXTILE MATERIAL FLAME PROOFED BY IMPREGNATING WITH REACTION PRODUCTS OF PHOSPHORYL CHLORIDE AND AMMONIA INVENTOR Josey)? LIOLTOMZ zi fiadf, 52% rm- ATTORNEYS United States Patent Ofiice 3,032,440 Patented May 1, 1962 3,032,440 FLAMEPROOFING NYLON-COTTON JERSEY KNIT Joseph L. Iannazzi, Lawrence, Mass, assignor to The General Tire & Rubber Company, Akron, Ohio, a corporation of Ohio Filed May 26, 1958, Ser. No. 737,627 21 Claims. (Cl. 117-138) This invention relates to the flameproofing of textiles and is particularly related to nylon-cotton jersey knitted fabrics which are treated with a mixture of phosphoryl chloride-ammonia reaction products.

The term flameproof as applied to fabrics implies a resistance to any spread of flame after the textile material has been ignited. Undyed, finish-free 100% nylon material will melt at a temperature of approximately 480 F. if a flame is applied, but is self-extinguishing in that upon removal of the flame, the melt will drop away and harden with little or no tendency for further flame propagation.

The presence of other textile fibers, even such materials as fiberglass or asbestos, though not flammable in themselves, with nylon will increase its tendency to burn.

The presence of amounts of solid materials such as antimony oxide, ammonium salts, borax, talc, etc. in powder form on nylon increases its tendency to burn. The molten drops of nylon are thickened by the foreign solids and cling to the remaining material instead of falling away; this in turn melts and ignites adjacent fabric thus propagating the flame.

The foregoing explains why most material used as flame retardants for other textile materials increases nylons flammability to an extent where a fiber blend, such as flameproofed cotton with nylon, will in effect result in an end product of a flammable nature.

Heretofore it has been proposed as seen in US. Patent No. 2,680,077 to use only a water insoluble product of phosphoryl chloride-ammonia to form a fire retarding coating on wood, paper, fabric and steel. I have now discovered that an improved fire retardant coating for knit fabrics, particularly mixtures of nylon and cotton, may be obtained by using a treating bath containing a mixture of water soluble and Water insoluble reaction products of phosphoryl chloride-ammonia.

According to the present invention, nylon-cotton fabrics are scoured or desized to remove foreign materials such as lubricating oils. The fabrics are thereafter rinsed, dried, and then dipped in an aqueous treating bath containing about 5 to 25 percent solids, which in turn comprise a mixture of water soluble and water insoluble reaction products of phosphoryl chloride-ammonia. The treated fabric is then dried at about 140 to 180 F. and then cured at about 250 to 300 F. for three to five minutes. During drying of the fabric at a raised temperature, insoluble compounds which produce the fire proofing effect are formed from the solids of the treating bath, probably in conjunction also with the nylon-cotton fibers. After drying, the treated fibers may be cold washed to obtain the desired feel in the finished fabric.

The mixture of reaction products of phosphoryl chloride (POCl and ammonia for best results should comprise about 70 to 80 percent by weight of a water insoluble reaction product although mixtures may be used which comprise about 50 to 90 percent of a water insoluble reaction product and to 50 percent of a water soluble reaction product of phosphoryl chloride and ammonia.

The water insoluble reaction product is described in US. Patent No. 2,680,077. The above material is a white powder insoluble in water and has a substantially neutral or alkaline reaction. The nitrogen/phosphorus atomic weight ratio of the polymeric material is in the range of 1.72 to l to 1.80 to 1. The water insoluble reaction product can be used alone without the water soluble reaction product, although when the nylon-cotton fabric contains more than 10 percent by weight of nylon, at least some water soluble reaction product should be used and preferably at least 5 to 10 percent of the water soluble product should be used based on the total weight of the mixture of the reaction products.

The water soluble reaction product is described in US. Patent No. 2,661,264 and is a white non-hygroscopic powder having a nitrogen/phosphorus weight ratio in the range of 2.1 to l to about 2.3 to 1. When dissolved in water, the resulting solution has a pH of about 7 to 8.

The knitted fabrics which are fiameproofed by the reaction products of phosphoryl chloride and ammonia are preferably cotton fiber mixtures with nylon in which the nylon content of the fibers is about 5 to 50 percent by weight of the total fiber content. The present invention provides a method of flameproolipg nyhgncOttoman,

The mixture of reaction products of phosphoryl.-chloride and ammonia is also particularly well' adapted to fireproofing other high melting synthetic fibers such as Dacron. Thus the nylon content of the above nylon cotton mixtures may be substituted in whole or part by Dacron fibers. Dacron is an oriented fiber of a polyester formed from ethylene glycol and terephthalic acid (polyethylene terephthalate fiber oriented along the fiber axis). Nylon is usually considered to be an oriented fiber of long-chain linear polymeric amides, such as hexamethylene diamine and adipic acid (polyhexamethylene adipamide or type 66 nylon), but also can be considered as an oriented fiber of polycapryl lactam which is commonly called Perlon or type 6 nylon. The term nylon may, therefore, be construed to include both hexamethylene adipamide and polycapryl lactam whenever employed in this application.

For best results in treating the nylon-cotton mixtures a wetting agent, such as sodium alkyl naphthalene sulphate, may be added to the treating bath to speed the pickup of flame retardant by the fabric. The wetting agents are generally used in amounts of about A; to percent by weight of the total bath. Other wetting agents may be used, such as alkyl benzene sodium sulphate nonionic, nonyl phenoxy polyoxethylene ethanol and fatty alcoholethylene oxide condensation products. Also suitable are tridecyl alcohol-ethylene oxide condensates and alkyl aryl sulphonates.

The accompanying drawing diagrammatically illustrates the present invention.

The following example illustrates the present invention:

Example A 25% nylon-% cotton knit jersey fabric was scoured to remove foreign material. The fabric was rinsed and dried and thereafter dipped in a flame retardant bath solution containing 15% by weight of solids according to the formula that follows.

ammonia) 15 Wetting agent: (Sodium alkyl naphthalene sulphonate) V2 The pick-up of bath solution by the nylon-cotton fabric was about 100 percent based on the weight of the fabric, or in other words, equal to the weight of the fabric which is about 10 oz. per yard. The treated jersey fabric was dried at 160 F. and thereafter heat treated at 275 F. for five minutes to provide a flame proof fabric. The pick-up of dried solids on the knitted fabric was 1.5 oz. per yard. When the treated fabric was subjected to accepted testing procedures for determining flammability, it was observed that the treated fabric slowed down the rate of burning and the fabric had no flame or afterglow when a heat source, such as the flame of a candle or a Bunsen burner was removed from contact with the fabric.

The temperature of the fabric during the drying of the Wet treated fabric is preferably held under about 180 F. to prevent possible deterioration of the coating, which apparently is due to hydrolysis of the water insoluble flame-proofing products formed on the fibers of the fabric.

It is obvious that many changes and modifications of this invention can be made within the nature and spirit thereof. It is, therefore, to be understood that the invention thereto is not limited except as set forth in the appended claims.

Having described my invention, I claim:

1. A composition comprising from about 50 to 95 percent by weight of the water insoluble reaction product of phosphoryl chloride and anhydrous ammonia and from 50 to percent by weight of the water soluble reaction product of phosphoryl chloride and ammonia.

2. A composition consisting essentially of from about 50 to 90 percent by weight of the water insoluble reaction product of phosphoryl chloride and anhydrous ammonia having a nitrogen to phosphorus ratio of from about 1.721 to 1.8:1 and from 50 to percent by weight of the water soluble reaction product of phosphoryl chloride and ammonia having a nitrogen to phosphorus ratio of from about 2.1:1 to 2.3:1.

3. A composition according to claim 2 in which said water insoluble reaction product is present in an amount of from about 70 to 80% by weight and said water soluble reaction product is present in an amount of from 30 to by Weight.

4. A composition according to claim 2 in which said water insoluble reaction product is present in an amount of from about 80 to 90% by weight and said water soluble reaction product is present in an amount of from 20 to 10% by weight.

5. A composition comprising water and from about 5 to percent by weight of solids, said solids comprising from about 50 to 95% by weight of the water insoluble reaction product of phosphoryl chloride and anhydrous ammonia and from 50 to 5% by weight of the water soluble reaction product of phosphoryl chloride and ammonia.

6. A composition consisting essentially of water and from about 5 to 25 percent by weight of solids, said solids comprising from about 50 to 90 percent by weight of the water insoluble reaction product of phosphoryl chloride and anhydrous ammonia having a nitrogen to phosphorus ratio of from about 1.7:1 to 1.8:1 and from 50 to 10 percent by weight of the water soluble reaction product of phosphoryl chloride and ammonia having a nitrogen to phosphorus ratio of from about 2.111 to 2.3:1.

7. A composition according to claim 6 containing additionally from about A; to percent by weight of said composition of a wetting agent.

8. A composition according to claim 7 wherein said water insoluble reaction product is present in an amount of from about 70 to 80% by weight and said water soluble reaction product is present in an amount of from to 20% by weight.

9. A composition according to claim 7 wherein said water insoluble reaction product is present in an amount 4 of from about to by weight and said water soluble reaction product is present in an amount of from 20 to 10% by weight.

10. A textile material having fibers containing a coating from a dried composition comprising from about 50 to by weight of the water insoluble reaction product of phosphoryl chloride and anhydrous ammonia and from 50 to 5% by weight of the water soluble reaction product of phosphoryl chloride and ammonia.

11. A textile fabric having fibers containing a fire retardant coating from a dried and cured composition consisting essentially of from about 50 to 90% by weight of the water insoluble reaction product of phosphoryl chloride and anhydrous ammonia having a nitrogen to phosphorus ratio of from about 1.721 to 1.8:1 and from 50 to 10% by weight of the water soluble reaction product of phosphoryl chloride and ammonia having a nitrogen to phosphorus ratio of from about 2.1 :1 to 23:1, said fibers comprising a mixture of cotton fibers and from about 5 to 50% by weight of fibers of a high melting point polymer.

12. A textile fabric according to claim 11 in which said high melting point polymer is present in said mixture in an amount of from about 10% to 50% by Weight of said mixture and is selected from the group consisting of nylon and polyethylene terephthalate and mixtures thereof.

13. A textile fabric according to claim 12 wherein said water insoluble reaction product is used in an amount of from about 70 to 80% by weight and said water soluble reaction product is used in an amount of from 30 to 20% by weight.

14. A textile fabric according to claim 12 wherein said water insoluble reaction product is used in an amount of from about 80 to 90% by weight and said water soluble reaction product is used in an amount of from 20 to 10% by Weight.

15. The method which comprises dipping a fabric into an aqueous treating bath containing from about 5 to 25% by Weight of solids comprising from about 50 to 95% by weight of the Water insoluble reaction product of phosphoryl chloride and anhydrous ammonia and from 50 to 5% by weight of the water soluble product of phosphoryl chloride and ammonia and heating said treated fabric to dry the same and provide a coating of said solids on the fibers of said fabric.

16. The method which comprises dipping a scoured fabric into an aqueous treating bath consisting essentially of water and from about 5 to 25% by weight of solids comprising from about 50 to 90% by weight of the water insoluble reaction product of phosphoryl chloride and anhydrous ammonia having a nitrogen to phosphorus ratio of from about 1.7:1 to 1.8:1 and from 50 to 10% by weight of the water soluble reaction product of phosphoryl chloride and ammonia having a nitrogen to phosphorus ratio of from about 2.1:1 to 2.3:1, said fabric comprising a mixture of cotton fibers and from about 5 to 50% by weight of fibers of a high melting point polymer, and drying and curing said treated fabric to provide a fire retardant coating on the fibers of said fabric.

17. The method according to claim 16 in which said drying step is conducted at a temperature of from about to F. and saidcuring step is conducted at a temperature of from about 250 to 300 F.

18. The method according to claim 17 in which said aqueous treating bath contains additionally from about A; to /1 by weight of said bath of a wetting agent.

19. The method according to claim 18 in which said high melting point polymer is present in said mixture in an amount of from about 10% to 50% by weight of said mixture and is selected from the group consisting of nylon and polyethylene terephthalate and mixtures thereof.

20. The method according to claim 19' wherein said water insoluble reaction product is used in an amount of from about 70 to 80% by weight and said water soluble reaction product is used in an amount of from 30 to 20% by weight.

21. The method according to claim 19 wherein said water insoluble reaction product is used in an amount of from about 80 to 90% by weight and said water soluble reaction product is used in an amount of from 20 to 10% by weight.

References Cited in the file of this patent UNITED STATES PATENTS Thomas et a1 June 4, 1946 Malowan Dec. 1, 1953 Jenkins Dec. 1, 1953 Nielsen et a1 June 1, 1954 Rossin June 11, 1957 

15. THE METHOD WHICH COMPRISES DIPPING A FABRIC INTO AN AQUEOUS TREATING BATH CONTAINING FROM ABOUT 5 TO 25% BY WEIGHT OF SOLIDS COMPRISING FROM ABOUT 50 TO 95% BY WEIGHT OF THE WATER INSOLUBLE REACTION PRODUCT OF PHOSPHORYL CHLORIDE AND ANYDROUS AMMONIA AND FROM 50 TO 5% BY WEIGHT OF THE WATER SOLUBLE PRODUCT OF PHOSPHORYL CHLORIDE AND AMMONIA AND HEATING SAID TREATED FABRIC TO DRY THE SAME AND PROVIDE A COATING OF SAID SOLIDS ON THE FIBERS OF SAID FABRIC. 